This could be an airleak after the airflow meter, any air dragged in here isn t seen by the ECU and thus not compensated for and can thin the engine out and can furthermore allow the engine to rev stirring in the manner of not desired causing sharp running. As its a mechanical deformity it tends not to slant on the aberration fresh and you can sometimes listen a hissing noise following the engine running.
Its then worth getting the fuel pressure checked as if this is low due to a blocked filter or faulty regulator or even a sick pump will every result in insufficient fuel visceral delivered to the engine. Might next be worth cleaning out the idle rapidity run motor / valve as these acquire clogged taking place following carbon and some brake cleaner washed through helps forgive things off.
I don't have any check engine lights unless I unplug the MAF sensor. bearing in mind the MAF is plugged in subsequently the car will stall unless I put my foot upon the accelerator. There is as a consequence an intermittent popping solid coming at idle.